Dual-Emission GFP Chromophore-Based Derivative for Imaging and Discriminating Aβ Oligomers and Aggregates.

β-Amyloid deposition is one of the main pathological features of Alzheimer's disease (AD). The development of fluorescent probes targeting specific β-amyloid species has recently become an attractive strategy to achieve the early diagnosis of AD. In this work, a dual-channel fluorescent protein chromophore derivative was rationally designed and synthesized for the detection and discrimination of Aβ aggregates and oligomers. exhibits a specific turn-on emission peak for Aβ oligomers at ∼470 nm (peak A) and a peak at ∼600 nm (peak B) for both Aβ oligomers and Aβ aggregates. Taking advantage of the dual emission of the probe, the dynamic aggregation process of the Aβ peptide was monitored in solution. Moreover, double staining of brain sections from transgenic AD mice revealed that peak A of preferentially detected Aβ oligomers, whereas peak B was more sensitive to Aβ aggregates. The fact that probe can be used for dissecting these two Aβ species makes a comprehensive tool for β-amyloid aggregation studies in AD research.